The present invention relates generally to addressing problems related to the digestive system, particularly obesity and type II diabetes. Additionally, it is contemplated that the methods and devices of the present invention may be used in treating other digestive conditions such as benign or malignant obstructions of the stomach, small bowel and/or colon when clinically indicated; peptic ulcer disease; inflammatory bowel disease; adhesions; annular pancreas; duodenal, pancreatic, intestinal, or colonic primary malignancies; and secondary malignancies.
Obesity
According to the Center for Disease Control (CDC), sixty six percent of the United States population are overweight, and thirty two percent are obese, presenting an overwhelming health problem. From an economic standpoint, it is estimated that more than 100 billion dollars are spent on obesity and treating its major co-morbidities. This figure does not include psychological and social costs. Many health care experts consider obesity the largest health problem facing westernized societies and consider obesity an epidemic. From a medical standpoint, obesity is the primary risk factor for type 2 diabetes and obstructive sleep apnea. It increases the chances for heart disease, pulmonary disease, infertility, osteoarthritis, cholecystitis and several major cancers, including breast and colon cancers. Despite these alarming facts, treatment options for obesity remain limited.
Treatment options include dietary modification, very low-calorie liquid diets, pharmaceutical agents, counseling, exercise programs and surgery. Diet and exercise plans often fail because most individuals do not have the discipline to adhere to such plans. When diet and exercise fail, many try dietary supplements and drugs or other ingestible preparations promoted as being capable of suppressing appetite or inducing satiety. In general, these techniques for treating compulsive overeating/obesity have tended to produce only a temporary effect. The individual usually becomes discouraged and/or depressed after the initial rate of weight loss plateaus and further weight loss becomes harder to achieve. The individual then typically reverts to the previous behavior of compulsive overeating.
Surgical procedures that restrict the size of the stomach and/or bypass parts of the intestine are the only remedies that provide lasting weight loss for the majority of morbidly obese individuals. Surgical procedures for morbid obesity are becoming more common based on long-term successful weight loss result.
Bariatric surgery is a treatment for morbid obesity that involves alteration of a patient's digestive tract to encourage weight loss and to help maintain normal weight. Known bariatric surgery procedures include jejuno-ileal bypass, jejuno-colic shunt, biliopancreatic diversion, gastric bypass, Roux-en-Y gastric bypass, gastroplasty, gastric banding, vertical banded gastroplasty, and silastic ring gastroplasty. A more complete history of bariatric surgery can be found on the website of the American Society for Bariatric Surgery at http://www.asmbs.org, the contents of which are incorporated by reference herein in their entirety.
The surgeries which create malabsorption, such as the by-pass operations, although effective in weight reduction, involve permanent modification of the GI tract and have a risk of short and long term complication and even death.
Gastric bypass is the most common weight loss operation in the United States. This procedure reduces the size of the stomach and shortens the effective-length of intestine available for nutrient absorption. With gastric bypass many investigators have reported weight loss results that exceed 70% of excess weight. However, this efficacy does not come without complication. The accepted mortality of the procedure is 1in 200. Additionally, because various sections of the intestine are responsible for absorbing various nutrients from the chyme being digested, bypassing sections of the intestine can result in an inability of the modified digestive tract to benefit from certain nutrients. In certain cases, this results in conditions such as anemia and must be treated with high doses of vitamin or nutrient supplements.
Diabetes
According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) an estimated 20.8 million people in the United States, 7.0 percent of the population, have diabetes, a serious, lifelong condition. Of those, 14.6 million have been diagnosed, and 6.2 million have not yet been diagnosed. In 2005, about 1.5 million people aged 20 or older were diagnosed with diabetes. According to the American Diabetes Association, the total annual economic cost of diabetes in 2002 was estimated to be $132 billion.
Diabetes is a set of related diseases in which the body cannot regulate the amount of sugar (glucose) in the blood. Glucose in the blood provides the body with energy. In a healthy person, the blood glucose level is regulated by several hormones including insulin, glucagons, and epinephrine. Insulin is produced by the pancreas, a small organ near the stomach that also secretes important enzymes that help in the digestion of food. Insulin allows glucose to move from the blood into the liver, muscle, and fat cells, where it is used for fuel.
At least 90% of patients with diabetes have Type 2 diabetes wherein the pancreas secretes insulin but the body is partially or completely unable to use the insulin. This is sometimes referred to as insulin resistance. The body tries to overcome this resistance by secreting more and more insulin. People with insulin resistance develop Type 2 diabetes when they do not continue to secrete enough insulin to cope with the higher demands.
Recently, evidence for reduction of complications of type 2 diabetes with tight control of hyperglycemia has been reported, but current therapies, including diet, exercise, behavior modification, oral hypoglycemic agents, and insulin, rarely return patients to euglycemia.
For reasons not completely known, the majority of patients who undergo gastric bypass surgery experience resolution of Type 2 diabetes and enjoy normal blood glucose and glycosylated hemoglobin levels with discontinuation of all diabetes-related medications. One hypothesis, that has been proposed, is that diabetes control results from the expedited delivery of nutrient-rich chyme (partially digested food) to the distal intestines, enhancing a physiologic signal that improves glucose metabolism, the so called “hindgut hypothesis”. However, because gastric bypass surgery is considered a relatively high-risk major surgery, it is not used to treat Type 2 diabetes.